src/com/android/launcher3/LauncherExtension.java

package com.android.launcher3;

import android.animation.Animator;
import android.animation.Animator.AnimatorListener;
import android.animation.AnimatorListenerAdapter;
import android.animation.ObjectAnimator;
import android.content.ComponentName;
import android.content.Intent;
import android.graphics.Rect;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;

import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.ArrayList;

/**
 * This class represents a very trivial LauncherExtension. It primarily serves as a simple
 * class to exercise the LauncherOverlay interface.
 */
public class LauncherExtension extends Launcher {

    //------ Activity methods -------//
    @Override
    public void onCreate(Bundle savedInstanceState) {
        setLauncherCallbacks(new LauncherExtensionCallbacks());
        super.onCreate(savedInstanceState);
    }

    public class LauncherExtensionCallbacks implements LauncherCallbacks {

        LauncherExtensionOverlay mLauncherOverlay = new LauncherExtensionOverlay();

        @Override
        public void preOnCreate() {
        }

        @Override
        public void onCreate(Bundle savedInstanceState) {
        }

        @Override
        public void preOnResume() {
        }

        @Override
        public void onResume() {
        }

        @Override
        public void onStart() {
        }

        @Override
        public void onStop() {
        }

        @Override
        public void onPause() {
        }

        @Override
        public void onDestroy() {
        }

        @Override
        public void onSaveInstanceState(Bundle outState) {
        }

        @Override
        public void onPostCreate(Bundle savedInstanceState) {
        }

        @Override
        public void onNewIntent(Intent intent) {
        }

        @Override
        public void onActivityResult(int requestCode, int resultCode, Intent data) {
        }

        @Override
        public void onWindowFocusChanged(boolean hasFocus) {
        }

        @Override
        public boolean onPrepareOptionsMenu(Menu menu) {
            return false;
        }

        @Override
        public void dump(String prefix, FileDescriptor fd, PrintWriter w, String[] args) {
        }

        @Override
        public void onHomeIntent() {
        }

        @Override
        public boolean handleBackPressed() {
            if (mLauncherOverlay.isOverlayPanelShowing()) {
                mLauncherOverlay.hideOverlayPanel();
                return true;
            }
            return false;
        }

        @Override
        public void onLauncherProviderChange() {
        }

        @Override
        public void finishBindingItems(boolean upgradePath) {
        }

        @Override
        public void onClickAllAppsButton(View v) {
        }

        @Override
        public void bindAllApplications(ArrayList<AppInfo> apps) {
        }

        @Override
        public void onClickFolderIcon(View v) {
        }

        @Override
        public void onClickAppShortcut(View v) {
        }

        @Override
        public void onClickPagedViewIcon(View v) {
        }

        @Override
        public void onClickWallpaperPicker(View v) {
        }

        @Override
        public void onClickSettingsButton(View v) {
        }

        @Override
        public void onClickAddWidgetButton(View v) {
        }

        @Override
        public void onPageSwitch(View newPage, int newPageIndex) {
        }

        @Override
        public void onWorkspaceLockedChanged() {
        }

        @Override
        public void onDragStarted(View view) {
        }

        @Override
        public void onInteractionBegin() {
        }

        @Override
        public void onInteractionEnd() {
        }

        @Override
        public boolean forceDisableVoiceButtonProxy() {
            return false;
        }

        @Override
        public boolean providesSearch() {
            return true;
        }

        @Override
        public boolean startSearch(String initialQuery, boolean selectInitialQuery,
                Bundle appSearchData, Rect sourceBounds) {
            return false;
        }

        @Override
        public void startVoice() {
        }

        @Override
        public boolean hasCustomContentToLeft() {
            return false;
        }

        @Override
        public void populateCustomContentContainer() {
        }

        @Override
        public View getQsbBar() {
            return mLauncherOverlay.getSearchBox();
        }

        @Override
        public Intent getFirstRunActivity() {
            return null;
        }

        @Override
        public boolean hasFirstRunActivity() {
            return false;
        }

        @Override
        public boolean hasDismissableIntroScreen() {
            return false;
        }

        @Override
        public View getIntroScreen() {
            return null;
        }

        @Override
        public boolean shouldMoveToDefaultScreenOnHomeIntent() {
            return true;
        }

        @Override
        public boolean hasSettings() {
            return false;
        }

        @Override
        public ComponentName getWallpaperPickerComponent() {
            return null;
        }

        @Override
        public boolean overrideWallpaperDimensions() {
            return false;
        }

        @Override
        public boolean isLauncherPreinstalled() {
            return false;
        }

        @Override
        public boolean hasLauncherOverlay() {
            return true;
        }

        @Override
        public LauncherOverlay setLauncherOverlayView(InsettableFrameLayout container,
                LauncherOverlayCallbacks callbacks) {

            mLauncherOverlay.setOverlayCallbacks(callbacks);
            mLauncherOverlay.setOverlayContainer(container);

            return mLauncherOverlay;
        }

        class LauncherExtensionOverlay implements LauncherOverlay {
            LauncherOverlayCallbacks mLauncherOverlayCallbacks;
            ViewGroup mOverlayView;
            View mSearchBox;
            View mSearchOverlay;
            boolean mShowOverlayFeedback;
            int mProgress;
            boolean mOverlayPanelShowing;

            @Override
            public void onScrollInteractionBegin() {
                if (mLauncherOverlayCallbacks.canEnterFullImmersion()) {
                    mShowOverlayFeedback = true;
                    updatePanelOffset(0);
                    mSearchOverlay.setVisibility(View.VISIBLE);
                    mSearchOverlay.setLayerType(View.LAYER_TYPE_HARDWARE, null);
                }
            }

            @Override
            public void onScrollChange(int progress, boolean rtl) {
                mProgress = progress;
                if (mShowOverlayFeedback) {
                    updatePanelOffset(progress);
                }
            }

            private void updatePanelOffset(int progress) {
                int panelWidth = mSearchOverlay.getMeasuredWidth();
                int offset = (int) ((progress / 100f) * panelWidth);
                mSearchOverlay.setTranslationX(- panelWidth + offset);
            }

            @Override
            public void onScrollInteractionEnd() {
                if (mProgress > 25 && mLauncherOverlayCallbacks.enterFullImmersion()) {
                    ObjectAnimator oa = LauncherAnimUtils.ofFloat(mSearchOverlay, "translationX", 0);
                    oa.addListener(new AnimatorListenerAdapter() {
                        @Override
                        public void onAnimationEnd(Animator arg0) {
                            mSearchOverlay.setLayerType(View.LAYER_TYPE_NONE, null);
                        }
                    });
                    oa.start();
                    mOverlayPanelShowing = true;
                    mShowOverlayFeedback = false;
                }
            }

            @Override
            public void onScrollSettled() {
                if (mShowOverlayFeedback) {
                    mSearchOverlay.setVisibility(View.INVISIBLE);
                    mSearchOverlay.setLayerType(View.LAYER_TYPE_NONE, null);
                }
                mShowOverlayFeedback = false;
                mProgress = 0;
            }

            public void hideOverlayPanel() {
                mLauncherOverlayCallbacks.exitFullImmersion();
                mSearchOverlay.setVisibility(View.INVISIBLE);
                mOverlayPanelShowing = false;
            }

            public boolean isOverlayPanelShowing() {
                return mOverlayPanelShowing;
            }

            @Override
            public void forceExitFullImmersion() {
                hideOverlayPanel();
            }

            public void setOverlayContainer(InsettableFrameLayout container) {
                mOverlayView = (ViewGroup) getLayoutInflater().inflate(
                        R.layout.launcher_overlay_example, container);
                mSearchOverlay = mOverlayView.findViewById(R.id.search_overlay);
                mSearchBox = mOverlayView.findViewById(R.id.search_box);
            }

            public View getSearchBox() {
                return mSearchBox;
            }

            public void setOverlayCallbacks(LauncherOverlayCallbacks callbacks) {
                mLauncherOverlayCallbacks = callbacks;
            }
        };
    }
}